Systems and method of coating an interior surface of an object

Abstract

A system for use in coating an interior surface of an object is provided. The system includes a vacuum chamber enclosure defining an interior cavity configured to receive the object, an anode positioned within the interior cavity of the vacuum chamber enclosure, and a cathode positioned within the interior cavity of said vacuum chamber enclosure such that a space between the anode and the cathode is at least partially defined by the interior surface of the object. At least a portion of the cathode vaporizes when current is supplied thereto such that vaporized cathode material coats the interior surface of the object.

What is claimed is: 
     
         1 . A system for use in coating an interior surface of an object, said system comprising:
 a vacuum chamber enclosure defining an interior cavity configured to receive the object;   an anode positioned within said interior cavity of said vacuum chamber enclosure; and   a cathode positioned within said interior cavity of said vacuum chamber enclosure such that a space between said anode and said cathode is at least partially defined by the interior surface of the object, wherein at least a portion of said cathode vaporizes when current is supplied thereto such that vaporized cathode material coats the interior surface of the object.   
     
     
         2 . The system in accordance with  claim 1 , wherein at least one of said anode and said cathode are sized for insertion through an open end of the object and into an interior cavity of the object. 
     
     
         3 . The system in accordance with  claim 2 , wherein a clearance is defined between the interior surface of the object and said at least one of said anode and said cathode when positioned in the interior cavity of the object. 
     
     
         4 . The system in accordance with  claim 1  further comprising an insulator extending over at least a portion of said cathode and configured to sustain electrical discharge on a face of said cathode when current is supplied to said cathode. 
     
     
         5 . The system in accordance with  claim 4 , wherein said insulator defines an exposed portion of said cathode, said insulator extending over said cathode such that said exposed portion is adjacent to said anode. 
     
     
         6 . The system in accordance with  claim 1  further comprising a gas supply tube configured to channel reactive gas to the interior cavity of the object. 
     
     
         7 . The system in accordance with  claim 6 , wherein the reactive gas comprises nitrogen. 
     
     
         8 . The system in accordance with  claim 1 , wherein the object includes a longitudinal axis extending along a length thereof, wherein at least one of said anode and said cathode are configured to translate along the longitudinal axis. 
     
     
         9 . The system in accordance with  claim 1  further comprising a voltage supply coupled to the object, wherein said voltage supply is configured to supply a voltage bias to the object. 
     
     
         10 . The system in accordance with  claim 1 , wherein the interior cavity of the vacuum chamber enclosure is evacuated to a pressure between about 10 −4  torr and about 10 −5  torr. 
     
     
         11 . A method of coating an interior surface of an object, said method comprising:
 providing a vacuum chamber enclosure defining an interior cavity configured to receive the object;   positioning the object within the interior cavity of the vacuum chamber enclosure;   positioning an anode within the interior cavity of the vacuum chamber enclosure;   positioning a cathode within the interior cavity of the vacuum chamber enclosure such that a space between the anode and the cathode is at least partially defined by the interior surface of the object; and   supplying current to the cathode to vaporize at least a portion of the cathode, wherein vaporized cathode material coats the interior surface of the object.   
     
     
         12 . The method in accordance with  claim 11  further comprising selecting a portion of the interior surface to be coated as a function of a location of at least one of the anode and the cathode. 
     
     
         13 . The method in accordance with  claim 11  further comprising translating at least one of the anode and the cathode relative to the object to coat the interior surface at different axial locations along a longitudinal axis of the object. 
     
     
         14 . The method in accordance with  claim 11  further comprising channeling reactive gas towards the interior cavity of the object to react with the vaporized cathode material. 
     
     
         15 . The method in accordance with  claim 14 , wherein channeling reactive gas comprises channeling the reactive gas towards the space between the anode and the cathode. 
     
     
         16 . The method in accordance with  claim 11  further comprising sizing at least one of the anode and the cathode for insertion through an open end of the object and into an interior cavity of the object. 
     
     
         17 . The method in accordance with  claim 16 , wherein sizing at least one of the anode and the cathode comprises defining a clearance between the interior surface of the object and at least one of the anode and the cathode when positioned in the interior cavity of the object. 
     
     
         18 . The method in accordance with  claim 11  further comprising supplying a voltage bias to the object to facilitate attracting the vaporized cathode material towards the interior surface of the object. 
     
     
         19 . The method in accordance with  claim 11 , wherein supplying current to the cathode comprises selecting an amount of current to supply that facilitates restricting molten coating material from being discharged towards the interior surface. 
     
     
         20 . The method in accordance with  claim 11  further comprising extending an insulator over at least a portion of the cathode to facilitate sustaining electrical discharge on a face of the cathode when current is supplied to the cathode.